10. The Great Pacific Garbage Patch (Northern Pacific)
The island is filled with tons of plastic junk piled almost everywhere. It is also considered to be the destroyer of sea animals. There is a high toxic level on the island due to a large amount of plastic dumped here near the sea.
11. Gruinard Island (Scotland)
The island is oval shaped and considered as one of the deadliest islands ever. Due to the biological warfare experiments of the British, the island was kept under secret. Scientists experimented with Anthrax, which killed all the local animals, as well as contaminated the soil.